Allium the Latin word given to garlic, a flowering
plant with hundreds of separate species;
which many have been gathered through human history, One of the species belong
to this (related group of living things) is the Allium sativum L. Also known as
the garlic, which is from onion family Alliaceae, shallot, leek, chive, and
rakkyo. The bulb called cloves with clear covering. They can easily grow in
different conditions from dry, well-drained mineral-based soil to moist organic
soil, most grow in sunny locations but a number also grow in forests, or even
in swap water areas.
Allium sativum L. consist of sulfur containing compounds
such as allicin, alliin, dially disulfide, dithiin and Sallylcysteine. These
large number of sulfur compounds responsible for the smell and taste of garlic.
Dially disulfide is most essential compound which contribute in distinct and
sharp odor in the garlic. Allicin gives the tartness of the raw garlic and it
is also a powerful antibiotic and antifungal compound, allicin majorly serves
as anti-inflammatory effect. Garlic contains essential oil, which is obtained by
the process of steam distillation of the garlic cloves using n-hexane as
solvent. Essential garlic oil comprises of range of sulfide such as dially
disulfide and dilly trisulfide. During the processing allicin is reduced from
the oil. Commercially available garlic oil capsules generally contain vegetable
oil and a little portion of garlic essential oil because of the pungent odors.Garlic
oil has plentiful uses in the world today, its uses include the flavouring in
cuisine like salads, and sauces. The garlic oil can lower and treated high blood
pressure if regularly consume, prevention from cardiovascular disease. Garlic
oil is an efficient anti-viral, antibiotic, anti-fungal agent, which can use in
prevention from diarrhea, cough and nausea. Some studies have found results
that it can also fight against cancer.
Sampling before testing done and removal of transparent
covering of garlic was removed manually and sun-dried for two weeks. Powdered
the dry garlic cloves, then sieved and stored in a covered plastic container.
The physiochemical analyses were carried out in triplication. The extraction of
garlic oil was accomplished with a soxhlet extractor using n-hexane (boiling
point of 40ºC – 60ºC) for six hours. The oil obtained under reduced temperature
and pressure and refluxing at 70ºC so the removal of solvent from extracted oil
product and recover solvent can be reused. The garlic oil was stored in freezer
at 2ºC for succeeding physicochemical analyses.
They obtained chemical analysis which can predict
oil quality such as peroxide value, iodine value, saponification value, free
fatty acid value, acid value by using standard methods. They also interpreted
physical parameters of garlic oil, such color which is light yellow, specific
gravity lower than water 0.9, odor pungent due to allicin and oil yield is
From chemical analysis of garlic oil they compare
their results with different oil like shea butter, cotton seed oil. Peroxide
value tells deterioration of oil due to oxidation. The low peroxide value 2.50
± 0.50% found from garlic oil when compared to palm kernel oil 3.58% indicates
that the oil can be kept for a very long period of time. Acid value: The acid
value 4.18 ± 0.01mgKOH/g obtained from the oil is low when compared to Sheanut
butter oil 10.3mgKOH/g and high when compared to 2.39 ± 0.065mgKOH/g, for
castor oil, thus the higher the acid value of an oil, the lower its storage
quality and vice-versa. It shows that the garlic oil have an tremendous storage
quality when compared to that of Sheanut butter oil. Free fatty acid (oleic
acid), determine the appropriateness of the oil for edibility or industrial
uses. The free fatty acid value is 2.10 ± 0.05% which is low when compared to
the Hyptus spicigera seed oil 3.50%, its shows that it is good for eating.
Iodine value determines the proportion of unsaturated acid or fat and oil
present, but the test determines the amount of iodine absorbed per gram of
sample. The determination of iodine value determines the reaction of the double
bonds with halogen. The iodine value 12.69 ± 0.05g/100g which was gained from
the oil is low when compared to 16.0g/100g Tiger nut oil. The oil shows quite degree
of unsaturated fatty acid which indicates that the oil is suitable for utilization.
They concluded from
results that garlic oil indicated good quality, chemical analyses presented
saponification value, peroxide value, acid value, free fatty acid and Iodine
values that fell within the range of those acceptable as having good potential
for soap production and with an tremendous storage property.